Electric circuit breaker



. Jan. 8, 1935. c. BRESSON ELECTRIC CIRCUIT BREAKER Filed Aug. 2, 1 933;

- (mar/2 Patented Jan. 8, 1935 I UNITED STATES ELECTRIC CIRCUIT BREAKER Charles Bresson, Vllleurbanne, France, assignor to Atelier-s de Constructions Electrlques. de

France Delle, Paris,

Application August 2, 1933, Serial No. 683,351 In Germany August 1, 1932 zen-1m.

Electric circuit-breakers are known in which the are is drawn out by displacement oi the movable contact in a chamber filled with a liquid, the stationary contact being located in said liquid 5 outside said chamber near an orifice in the latter, said orifice constituting a e for the movable contact as well as a nozzle for the partial escape of the contents oi the chamber subjected to pressure through the influence oi the arc. In

such a device, the movable contact at the end of the operation of opening is completely withdrawn from the chamber by issuing through a second orifice situated at the lower part of the According to the present invention, the opstation 01' this circuit-breaker is improved by increasing the height of the chamber which, in accordance with the invention, should be at least equal to oi'the maximum separation oi fire Bythe expression height oi the chamber" must be understood the mean distance separating the narrowest zones of the two orifices through which passes the. movable contact. 5 The invention and its aims and objects will be readily understood from the following description taken in connection with the accom tic drawing or one illustrative embodiment of the invention. l V In the drawing,'the chamber containing the liquid, which may be insulating or conducting,

is indicated by 1, the upper stationary contact by 2 and the lower movable contact shown in open pomtion by 3. The chamber is terminated i at top and bottom bynozzles 4 and 5 through which passes the movable contactshown in chaindotted lines in closed position. The nomle 5 is larger than the diameter of the contact 3 so as to enable the gases developed by the arc to escape v through this nozzle during'the displacement of the contact within the chamber 1. In certain exceptional cases the lateral walls of the chamber may be provided with orifices 6'. The whole is disposed within a vesel 7 containing the liquid.

The operation of the circuit-breaker is as follows: on opening the circuit-breaker the contact 3 is lowered to the position in which it is shown in the drawing, and, as a consequence, the arc ck between 2 and 3 is drawn into the'chamber in which it vaporizes a part of the contained liquid. This vaporization creates a rise in pressure which provokes the expulsion of liquid and gases through the nozzles 3 or 4. on emerging from the nozzles these jets spread out, expand and are cooled. 0n the first passage of the current through zero-a regenerated medium is thus 6 created between the two contacts and as a result the striking voltage between the latter attains a high value and restriking oi the arc is prevented. This eflect even takes place when the pressure is only 01' the order of a few atmosl0 pheres.

It is evident that the invention is inno way limited to the vertical displacement of the movable contact and that the latter may move away from the stationary contact in any other direction whatsoever. On the other hand, the lower contact may be stationary and disposed below the chamber whilst the upper \c ontact will consequently be movable.

Having now particularly described and ascer- .tained thenature of my said invention and in what manner the same is to be clare that what I claim is:

a 1. In an electric circuit-breaker, an upper and a lower contact, said contacts being relatively movable and disposed in a liquid contained in a vessel, a chamber with upper and lower openings disposed within said vessel, the diameter or said openings being greater than that of said lower contact, said lower contact in closed position of the circuit-breaker traversing said chamber through the two openings and leaving said chamher by the lower opening; the height of said chamber being at least equal to of the maximum separation of the two said contacts.

2. In an electric circuit-breaker, an upper and a lower contact, said contacts=-being relatively performed, I de .movable and dispoud in a liquid contained in a vessel, a chamber with upper and lower openings disposed within said vessel, the diameter oi said openings being greater than that of-said lower contact, said openings constituting nozzles the interior walls oi. which are first convergent and then divergent, said lower contact in closed position of the circuit-breaker traversing said chamher through the two nozzles and leaving said chamber by the lower nozzle, the height of said chamber being at least equal to of the maximum separation of the two contacts.

(mamas BRESSON. 

